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<title>Niall Murphy</title>
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<img scale=25 src="portrait-smallest-cut.jpg" alt="Me in the Valle de Ordesa in the Pyrenees."/>
<h1>Niall Murphy</h1>
Ναϊλ Μερφη</br>
Найл Мерфи</br>
Նէալ Մօրֆի</br>
नाइल मर्फी </br>
నాయల్ మర్ఫీ </br>
ไนเอล เมอร์ฝีย์ </br>
נייל מורפי</br>
نايل مورفي</br>
耐尔 墨菲</br>
나일 머피</br>
ナイル マーフィー</br>
なぃる まーふぃー</br>
</div>
<div id="intro">
<h2><a id="maincontent"></a>Summary</h2>
<p>
I am a Research Associate with <a href="http://www.slcu.cam.ac.uk/directory/locke-james">James Locke</a>
at the <a href="http://http://www.slcu.cam.ac.uk">The Sainsbury Laboratory</a> at the <a href="https://www.cam.ac.uk/">University of Cambridge</a>.
I am also a contract scientist at the
<a href="https://research.microsoft.com/en-us/groups/biology/">Bio-Computation group at Microsoft Research Cambridge, UK</a>
working on synthesising chemical reaction networks to compute particular functions.
<br/>
Previously, I was a postdoctoral fellow working with
<a href="http://www.lia.upm.es/index.php?page=alfonso-rodriguez-paton-aradas">Alfonso Rodríguez-Patón</a>
and the <a href="http://www.lia.upm.es/">LIA group</a>
in <a href="http://www.fi.upm.es/">Faculty of Informatics in the Universidad Politécnica de Madrid</a>.
</p>
<p>
My research interest lies in the intersection of biology and computation.
Current projects and interests include, in no particular order:
<ul>
<!--<li>Studying the spread of plasmids in bacterial colonies by conjugation.</li>
<li>Understanding co-evolution between bacteria and bacteriophages.</li>-->
<li>Controlling spatial pattern formation in bacterial colonies.</li>
<li>Chemical reactions/gene networks as information processing systems.</li>
</ul>
My approach is to express these systems using existing models from
computer science and the analyse the computing potential of these systems
or use existing results from computer science to form new biological hypotheses.
</p>
<!--<p>Here is my first plasmid.
</br>
<img src="plasmidrs.jpg">
</p>-->
<p>
My PhD thesis was on identifying what classes of problems can be
tackled by an abstract mathematical model of cellular division.
My special focus was on problems that could be solved using a
feasible amount of time and very little memory (molecules).
<em>"Uniformity conditions for membrane systems: Uncovering complexity below P"</em>
(<a href="papers/thesis.pdf">pdf</a>),
and is from the <a href="http://www.cs.nuim.ie">Computer Science Department</a>
of <a href="http://www.nuim.ie">NUI Maynooth</a>.
My supervisors were <a href="http://www.dna.caltech.edu/~woods/">Damien Woods</a> and <a href="http://www.cs.may.ie/~tnaughton/">Tom Naughton</a>.
I defended my thesis in March 2010.
<!--and my examiners were <a href="http://axpsu.fpf.slu.cz/~sos10um/">Petr Sosík</a>
and <a href="http://www.cs.nuim.ie/~pmoser/">Philippe Moser</a>.-->
</p>
</div>
<div class="clear"></div>
<!--<h3 class="headerstyle">Latest Result</h3>
<p>
N. Murphy and D. Woods <em>A characterisation of NL using membrane systems without charges and dissolution</em>, NUIM Tech Report NUIM-CS-TR-2008-01, Jan 2008, Department of Computer Science, National University of Ireland Maynooth, Ireland.
<a href="papers/MW2008m.pdf">pdf</a>
</p>-->
<h3 class="headerstyle">Publications by topic</h3>
<!--
<p>My <a href="http://www.informatik.uni-trier.de/~ley/db/indices/a-tree/m/Murphy:Niall.html">DBLP</a> page.
The publications are arranged by topic
<p class="rev-conf">N. Murphy & A. odríguez-Patón
<em>"Distributed Computing With Prokaryotic Immune Systems"</em>
, the following colours indicate the status of the publication.
<span class="journal">Journal Papers</span>, <span class="rev-conf">Reviewed Conference papers</span>, <span class="unrev-conf">Unreviewed conference papers</span>, <span class="tech">Unreviewed Technical Reports and preprints</span>.-->
<!--<p class="tech">
N. Murphy & D. Woods. <em>"The Computational Complexity of Uniformity and Semi-uniformity in Membrane Systems"</em>, Technical Report in 7th Brainstorming Week on Membrane Computing, Volume 2, 73-84
<a href="papers/MW2009cb.pdf">pdf</a> <a href=papers/me-refs.bib>bibtex</a>
</p>-->
<p class="block"><strong>Synthesising Chemical Reaction Networks</strong></p>
<p class="rev-conf">N. Dalchau, N. Murphy, R. Petersen, B. Yordanov
<em>"Synthesizing and tuning chemical reaction networks with specified behaviours"</em>
21st Conference on DNA Computing and Molecular Programming Machines. 2015
<a href="https://arxiv.org/abs/1508.04403">arXiv:1508.04403 [cs.ET]</a>
<p class="block"><strong>Natural Computing</strong></p>
<p class="rev-conf">N. Murphy & A. Rodríguez-Patón
<em>"Distributed Computing With Prokaryotic Immune Systems"</em>
ICARIS 2012, Workshop on Bio and Immune Inspired Algorithms and Models for Multi-Level Complex Systems, Sept 2012. Springer LNCS Vol. 7597
<a href="papers/MR2012a.pdf">pdf</a> <font color="red">
(Invited speaker)</font></p>
<!--<p class="tech">
N. Murphy, D. Woods and T.J. Naughton, <em>"Stable Sorting Using Special-Purpose Physical Devices"</em>, BCRI Preprint 06/2006, May 2006, Boole Centre for Research in Informatics, University College Cork, Ireland.
<a href="papers/MWN2006m.pdf">pdf</a> <a href="papers/me-refs.bib">bibtex</a>
</p>-->
<p class="unrev-conf">N. Murphy, D. Woods and T.J. Naughton, <em>"Bio-Computation using Holliday junctions"</em>, 4th International Conference on Information and 4th Irish Conference on the Mathematical Foundations of Computer Science and Information Technology (MFCSIT), pp. 317-320, Cork, Ireland, 1-5 August 2006.
<a href="papers/MWN2006c.pdf">pdf</a>
</p>
<p class="tech">
N. Murphy, D. Woods and T.J. Naughton, <em>"On the computational complexity of photosynthesis"</em>, NUIM Tech Report NUIM-CS-TR-2005-03, Sept 2005, Department of Computer Science, National University of Ireland Maynooth, Ireland.
<a href="papers/MWN2005m.pdf">pdf</a>
</p>
<p class="block"><strong>Computational complexity and membrane systems.</strong></p>
<p class="tech">
Niall Murphy and Damien Woods
<em>"AND and/or OR: Uniform polynomial-size circuits"</em>,
<a href="http://arxiv.org/abs/1212.3282">arXiv:1212.3282 [cs.CC]</a>
Dec 2012 <!--<a href="">pdf</a>-->
</p>
<p class="tech">
Antonio E. Porreca, Niall Murphy, and M.J. Pérez-Jiméz
<em>"An Optimal Frontier of the Efficiency of Tissue P Systems with Cell Division"</em>,
In Proceedings of the 10th Brainstorming Week on Membrane Computing, 2012.
<a href="papers/PMP2012.pdf">pdf</a>
</p>
<p class="unrev-conf">N. Murphy & D. Woods. <em>"Uniformity: Uncovering the Frontier of Parallelism"</em>, Proceedings of the 10th Workshop on Membrane Computing, Curtea de Argeş, Romania. 2009. pages 556-560. <a href="papers/MW2009cc.pdf">pdf</a>
</p>
<p class="rev-conf">N. Murphy & D. Woods. <em>"A characterisation of NL using membrane systems without charges and dissolution"</em>, Proceedings 7th International Conference on Unconventional Computing 2008, Vienna, Austria. Springer Lecture Notes in Computer Science, vol 5204 , pp 164-176
<a href="papers/MW2008c.pdf">pdf</a>
<a href="http://www.springerlink.com/content/35qg210662026701/">Link</a>
</p>
<!--<p>
N. Murphy and D. Woods <em>A characterisation of NL using membrane systems without charges and dissolution</em>, NUIM Tech Report NUIM-CS-TR-2008-01, Jan 2008, Department of Computer Science, National University of Ireland Maynooth, Ireland.
<a href="papers/MW2008m.pdf">pdf</a>
</p>-->
<!--</div>-->
<p class="block" id="show_summary_uniform"><strong>Uniform families vs. Semi-uniform families.</strong></p>
<div class="blurb" id="summary_uniform">
<p>
When solving problems with biological computers, it sometimes seems more
intuitive to directly encode a problem instance into the computation machinery.
For example, many of the first DNA computers directly encoded problem instances
into experimental protocols so that a
unique protocol was required for each instance of the problem considered.
This way of encoding a problem is known as <em>semi-uniformity</em> in contrast
to the more general <em>uniformity</em> (e.g.\ Boolean circuits) where there is one device to solve all
problem instances of a certain size.
Previously most researchers intuitively felt that while uniformity was more
desirable than semi-uniformity the two concepts were computationally identical.
We show that for a simple class of circuits, uniform families are strictly weaker than
semi-uniform ones.
This result is applicable to any implementation of family style computing
systems (e.g. Boolean circuits, membrane systems, DNA strand displacement etc.).
</p>
</div>
<div class="main_paper" id="show_summary_uniform_memdiffuni">
<b>N. Murphy</b>, D. Woods
<em>"Uniformity is weaker than semi-uniformity for some membrane systems"</em>
<a href="http://dx.doi.org/10.3233/FI-2014-1095">
Fundamenta Informaticae
</a>, 134(1-2):129-152. 2014.
Also see <a href="http://arxiv.org/abs/1412.3377">arXiv:1412.3377 [cs.CC]</a>.
</div>
<!--<div class="blurb" id="summary_uniform_memdiffuni">
<p>
</p>
</div>-->
<div class="superceeded_paper" id="show_summary_uniform_dnapaper">
<p class="rev-conf">N. Murphy & D. Woods. <em>"Uniformity conditions in natural computing"</em>, preproceedings of DNA16 2010.
<!--<a href="papers/DNA16.pdf">pdf</a>-->
<!--<a style="color:red" href="http://nicosia.is.s.u-tokyo.ac.jp/dna/award.html">(Best student paper award)</a>-->
<a style="color:red" href="http://www.isnsce.org/awards/dna-student-awards">(Best student paper award)</a>
<!--The work in this paper was greatly expanded and its latest incarnation appears as -->
<!--"AND and/or OR: Uniform polynomial-size circuits"</em>,-->
<!--<a href="http://arxiv.org/abs/1212.3282">arXiv:1212.3282 [cs.CC]</a>.-->
</p>
</div>
<div class="blurb" id="summary_uniform_dnapaper">
<p>
<!--here we apply the result to membrane systems.-->
</p>
</div>
<div class="main_paper" id="show_summary_uniform_tight">
<p>N. Murphy & D. Woods.
<em>"The computational power of membrane systems under tight uniformity conditions"</em>
<a href="papers/IntroUniformity.pdf">pdf</a> (Invited)
Natural Computing: Volume 10, Issue 1 (2011), Page 613.
<a href="http://www.springerlink.com/content/m3361414614784kg/">Link</a>.
<!--<a href="agap-semi-uniform">code to generate the semi-uniform family solving AGAP (P-lingua)</a>-->
</p>
</div>
<div class="blurb" id="summary_uniform_tight">
<p>
We introduce tight (more appropriate) uniformity conditions to
membrane computing and find that some models are actually exponentially
weaker than previously thought.
</p>
</div>
<div class="superceeded_paper" id="show_summary_semiuniform_L_NL">
<p> N. Murphy & D. Woods.
<em>"On acceptance conditions for membrane systems: characterisations of L and NL"</em>,
The Complexity of Simple Programs, Cork, Ireland, 6-7 December, 2008.
Cork University Press, pages 225-242.
EPTCS volume 1 pages 172-184 <a href="http://arxiv.org/abs/0906.3327v1">arXiv:0906.3327v1 [cs.CC]</a>
<a href="papers/MW2008cb.pdf">pdf</a>
</p>
</div>
<div class="blurb" id="summary_semiuniform_L_NL">
<p>
Some definitions is the world of membrane systems are vague and open to
interpretation.
In this paper we consider some interpretations of the halting and acceptance conditions.
It is surprising that this can result in a change in the computing power of the system.
This idea was revisited more throughly in "<em>Uniformity is weaker than semi-uniformity for some membrane systems</em>" above.
</p>
</div>
<div class="superceeded_paper" id="show_summary_semiuniform_NL">
<p> N. Murphy & D. Woods.
<em>"A characterisation of NL using membrane systems without charges and dissolution"</em>
Unconventional Computing 7, 2008.
LNCS 5204, 164--176.
<a href="papers/MW2008c.pdf">pdf</a>
</p>
</div>
<div class="blurb" id="summary_semiuniform_NL">
<p>
We introduce tight (more appropriate) uniformity conditions to
membrane computing and find that some models are actually exponentially
weaker than previously thought.
This idea was revisited more throughly in "<em>The computational power of membrane systems under tight uniformity conditions</em>" above.
</p>
</div>
<p class="block" id="show_summary_Hasenjaeger"><strong>Hasenjaeger's universal machine.</strong></p>
<div class="blurb" id="summary_Hasenjaeger">
<p>
In the early 1960's Gilbert Hasenjaeger built several mechanical devices
to demonstrate the concept of a Turing machine
to his students at the Universities of Münster and Bonn.
Using old telephone relays and rotary switches forced him to build a machine
that uses remarkably few rules and to simulate a simple
non-erasing model, namely Wang's B machines.
</p>
<img src="GHutm-total.jpg" width=100%>
<p>
B machines have been used to
show that a number of other models are universal over the past 60 years.
Unfortunately, via
previous proofs, these models suffered from an exponential slowdown
when simulating Turing machines. We show that Wang's B
machines actually simulate Turing machines in polynomial time.
</p>
<p>
Since Hasenjaeger's machine simulates Wang B machines,
it too is an efficient model of computation.
</p>
<p>
Hasenjaeger's machine is currently on display in the Heinz Nixdorf MuseumsForum, Germany, and
a video of the machine in action can be seen
<a href="http://www.math.uni-hamburg.de/home/loewe/CL2012/">here</a>
or <a href="http://www.math.uni-hamburg.de/home/loewe/CL2012/hasenjaegermaschine.mp4">here</a>.
</p>
</div>
<div class="main_paper" >
Turlough Neary, Damien Woods, <b>Niall Murphy</b>, Rainer Glaschick
<em>"Wang's B machines are efficiently universal, as is Hasenjaeger's small universal electromechanical toy"</em>
to appear in the
<a href="http://dx.doi.org/10.1016/j.jco.2014.02.003">
Journal of Complexity
</a>, February 2014.
Also see <a href = "http://arxiv.org/abs/1304.0053">arXiv:1304.0053 [cs.CC]</a>.
</div>
<!--<div class="superceeded_paper" >-->
<!--Turlough Neary, Damien Woods, <b>Niall Murphy</b>, Rainer Glaschick-->
<!--<em>"Wang's B machines are efficiently universal, as is Hasenjaeger's small universal electromechanical toy"</em>-->
<!--<a href = "http://arxiv.org/abs/1304.0053">arXiv:1304.0053 [cs.CC]</a>-->
<!--March 2013-->
<!--</div>-->
<div class="superceeded_paper" >
<!--<div class="main_paper" >-->
R. Glaschick, T. Neary, D. Woods, and <b>N. Murphy</b>
<em>"Hasenjaeger's electromechanical small universal Turing machine is time efficient"</em>
<a href="http://www.computing-conference.ugent.be/tic2">Turing in context II</a>,
10-12th October 2012, Brussels, Belgium.
Contactforum Series of the Royal Flemish Academy of Sciences and Arts.
</div>
<p class="block" id="show_summary_PConjecture">
<strong>The P-Conjecture and the computational power of cellular division.</strong>
</p>
<div class="blurb" id="summary_PConjecture">
<p>
<a http="http://ppage.psystems.eu/">Membrane systems, or P-systems</a>
are a model of computation that abstracts the inner workings of
cells. Using this model we can characterise
the sets of problems that membrane systems can solve with limited
resources.
The hope is that as efforts to implement cellular computers progress
that the theoretical results from membrane systems will be a guide to
synthetic biologists as to how different cellular mechanisms
affect the computing power of the resulting cell.
</p>
<p>
Cell division seems to allow computers implemented in living cells
to create an exponential number of self-replicating parallel computing devices.
While in the real world, this level of perfect parallelism is impossible,
some level of parallelism is often desirable.
</p>
<p>
The <em>P-Conjecture</em>, stated in 2007 asks what features of
membrane computing are essential to take advantage of the exponential
growth of membrane systems. In particular it asks: if cells have
no way to indicate an internal change of state to the outside world,
can the overall system be parallel?
</p>
<p>
For a system to be parallel we show that it can solve problems in
<a http="http://en.wikipedia.org/wiki/PSPACE">PSPACE</a>
in polynomial time, or problems in
<a http="https://en.wikipedia.org/wiki/NC_(complexity)">NC</a>
in poly-logarithmic time.
To show a system is sequential, that is, that it probably (assuming that NC ≠ P, or P ≠ PSPACE)
can never be parallelised, we show that it exactly characterises
the complexity class <a http="https://en.wikipedia.org/wiki/P_(complexity)">P</a>.
</p>
<p>
The original statement of the P-Conjecture remains unsolved, but
my co-authors and I have made significant progress.
</p>
</div>
<!--<h3 class="cite" >[Symmetric]</h3>-->
<div class="main_paper" id="show_summary_PConjecture_Symmetric">
<b>N. Murphy</b> & D. Woods.
<em>"Active Membrane Systems Without Charges and Using Only Symmetric Elementary Division Characterise P"</em>
Proceedings of the Workshop on Membrane Computing 2007,
<a href="http://dx.doi.org/10.1007/978-3-540-77312-2_23">Springer LNCS vol. 4860, 367-384</a>.
<a href="papers/MW2007p.pdf">pdf</a>
</div>
<div class="blurb" id="summary_PConjecture_Symmetric">
<p>
This paper is the closest result to finally resolving the P-Conjecture.
We showed that if both daughter cells resulting from a division
are identical, that is the division was symmetric, that the system
probably cannot solve problems in a parallel way.
By storing just a single copy of each archetype membrane
and then manipulating counters as the system develops over time
we can simulate such a system in a standard
computer using polynomial time and memory.
</p>
</div>
<!--<h3 class="cite" >[Dissonly]</h3>-->
<div class="main_paper" id="show_summary_PConjecture_Dissonly">
D. Woods, <b>N. Murphy</b>, M.J. Pérez-Jiménez, A. Riscos-Núñez.
<em>"Membrane dissolution and division in P"</em>,
Proceedings of the 8th International Conference on Unconventional Computing 2009,
<a href="http://dx.doi.org/10.1007/978-3-642-03745-0_28">Springer LNCS vol. 5715 pp 262-276</a>.
<a href="papers/WMPR2009.pdf">pdf</a>
</div>
<div class="blurb" id="summary_PConjecture_Dissonly">
<p>
In this paper we consider a system that uses only two rules,
cell division and cell dissolution. These rules were key
to providing parallelism in other P-conjecture attempts.
We showed that with just this combination that the exponential number of membranes
can be compressed into a polynomially sized tree and that by
following the movement of objects around this tree needs only polynomial time.
</p>
</div>
<div class="main_paper" id="show_summary_PConjecture_divlevel">
Antonio E. Porreca and <b>Niall Murphy</b>.
<em>"First steps towards linking membrane depth and the Polynomial Hierarchy"</em>,
In Proceedings of the 8th Brainstorming Week on Membrane Computing, 2010.
<a href="papers/PM2010bwmc.pdf">pdf</a>
</div>
<div class="blurb" id="summary_PConjecture_divlevel">
<p>
In this technical report we find a possible link between the degree of
power of division in a system, and the resulting degree of parallelism.
We hope that by trying to characterise the Polynomial Hierarchy we
would gain insight into the P-Conjecture.
</p>
</div>
<p class="block" id="show_summary_Sorting"><strong>Models of Physical Sorting.</strong></p>
<div class="blurb" id="summary_Sorting">
<p>
There are theoretical limits on how fast we can sort a list of numbers.
However, in their daily activities, physical scientists routinely sort
millions of molecules.
In fact, the number of molecules being sorted does not affect the time
needed. Instead the resolution of the sorted list increases with time.
<p>
For example, microbiologists sort millions of DNA molecules by length.
<img src="gel-sort--wo-normal-ladder--aligned_26-4-06.png" width=100%>
(Image supplied by
<a href="http://www.ncbi.nlm.nih.gov/pubmed/?term=Beverley+Henley">Beverley Henley</a>
and
<a href="http://publish.ucc.ie/researchprofiles/C003/kmcd">Kieran McDermott</a>.)
</p>
<p>
Similarly, a prism can sort innumerable beams of light according to
their wavelength.
<img src="prism.png" width=100%>
</p>
<p>
Could it be possible to use a special purpose hardware component that
we could plug into a standard computer to sort in constant time?
We look at several processes:
gel electrophoresis,
chromatography,
optical tweezers,
refraction of light, and
mass spectrometry.
From these we abstract a model of computation that captures
a general method of physical sorting.
While this model allows us to sort a list in constant time,
there is a major bottle neck.
For such a device to be useful it must connect with a standard computer,
such as a
Turing machine or
Boolean circuit.
Unfortunately,
inputting the list to sort or reading off the output
makes our super fast sorting device behave just as poorly as
a standard sequential algorithm.
</p>
</div>
<p class="main-paper">
N. Murphy, T.J. Naughton, D. Woods, B. Henley, K. McDermott, E. Duffy, P. J. M. van der Burgt, and N. Woods,
<em>"Implementations of a model of physical sorting"</em>
2008, vol 4,8 pp 3-12,
International Journal of Unconventional Computing.
<a href="papers/MNWHDDBW2008p.pdf">pdf</a>
</p>
<p class="conference">
N. Murphy, T.J. Naughton, D. Woods, B. Henley, K. McDermott, E. Duffy, P. J. M. van der Burgt, and N. Woods,
<em>"Implementations of a model of physical sorting"</em>,
Sept 2006,
From Utopian to Genuine Unconventional Computers,
Part of the 5th International Conference on Unconventional Computation (UC 2006),
pp. 79-99, Luniver Press. ISBN: 0-9551170-9-7.
<a href="papers/MNWHDDBW2006c.pdf">pdf</a>
</p>
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<h3>Email Address</h3>
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<h3>Funding</h3>
<p>
Currently funded by Microsoft Research and the Gatsby foundation.
</p>
<!--Postdoctoral fellowship funded by the PICATA program of
<p>
<a href="http://www.cobra-project.eu/exchange_visits.html">the COBRA Project</a>.
<a href="http://www.campusmoncloa.es">CEI Moncloa</a>.
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<h3>News</h3>
<h4>July 2015</h4>
<p>
Joining the Locke Group at the Sainsbury Lab to continue work on
division of labour in bacterial biofilms.
</p>
<h4>May 2015</h4>
<p>
Our paper
"Synthesizing and tuning chemical reaction networks with specified behaviours"
has been accepted by the DNA 2015 conference in Harvard.
<a href="https://arxiv.org/abs/1508.04403">arXiv:1508.04403 [cs.ET]</a>
</p>
<h4>February 2014</h4>
<p>
Our paper
"Wang's B machines are efficiently universal, as is Hasenjaeger's small universal electromechanical toy"
has been accepted for publication in the
<a href="http://dx.doi.org/10.1016/j.jco.2014.02.003">
Journal of Complexity</a>.
</p>
<h4>November 2013</h4>
<p>
Deadline for the
<a href="http://www.cs.ox.ac.uk/conferences/CBIBM/">
Workshop on Cell Based and Individual Based Modelling - CBIBM
</a> is January the 6th 2014.
</p>
<h4>October 2013</h4>
<p>
Starting a new role with the Bio-Computation Group in Microsoft Research Cambridge, UK.
</p>
<h4>July/September 2013</h4>
<p>Paper "AND and/or OR: Uniform polynomial-size circuits"
<a href="http://arxiv.org/abs/1212.3282">arXiv:1212.3282 [cs.CC]</a>
is accepted for <a href="http://mcu2013.ini.uzh.ch">MCU 2013, ETH Zurich</a>, September 2013.
</p>
<h4>June 2013</h4>
<p>I am visiting the <a href="https://research.microsoft.com/en-us/groups/biology/">Bio Computation Group, Microsoft Research Cambridge, UK</a> this summer with funding from <a href="http://www.cobra-project.eu/exchange_visits.html">the COBRA Project</a>.
<h4>April 2013</h4>
<p>Report "Wang's B machines are efficiently universal, as is Hasenjaeger's small universal electromechanical toy"
<a href = "http://arxiv.org/abs/1304.0053">arXiv:1304.0053 [cs.CC]</a>
</p>
<h4>Dec. 2012</h4>
<p>Report "AND and/or OR: Uniform polynomial-size circuits"
<a href="http://arxiv.org/abs/1212.3282">arXiv:1212.3282 [cs.CC]</a>
</p>
<h4>Oct. 2012</h4>
<p>Paper "Hasenjaeger's electromechanical small universal Turing machine is time efficient" presented at <a href="http://www.computing-conference.ugent.be/tic2">Turing in Context II</a> 10-12 October 2012.
</p>
<h4>Sept. 2012</h4>
<p> Invited speaker at
<a href="http://www.artificial-immune-systems.org/icaris/2012/workshop.php">ICARIS 2012</a> Workshop on Bio and Immune Inspired Algorithms and Models for Multi-Level Complex Systems.
<p> Presented synthetic biology applications for plasmid biology at <a href="http://www.ispb2012.unican.es/">ISPB-2012</a>, the biannual meeting of the International Society of Plasmid Biology.
</p>
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